Notes on VMware Workstation 4.5.2 Beta - Using VMware Virtual Disk Manager
VMware Virtual Disk Manager is a utility in VMware Workstation that allows you to create, manage and modify virtual disk files from the command line or within scripts.
One key feature is the ability to enlarge a virtual disk so its maximum capacity is larger than it was when you created it. This way, if you find you need more disk space in a given virtual machine, but you do not want to add another virtual disk or use ghosting software to transfer the data on a virtual disk to a larger virtual disk, you can instead change the maximum size of the virtual disk. This is something you cannot do with physical hard drives.
Another feature allows you to change disk types. When you create a virtual machine, you specify how disk space is allocated. You select one of the following:
- All space for the virtual disk is allocated in advance. This corresponds to what the virtual disk manager callls the preallocated disk type.
- Space allocated for the virtual disk begins small and grows as needed. This corresponds to what the virtual disk manager calls the growable disk type.
With virtual disk manager you can change whether the virtual disk type is preallocated or growable and whether the virtual disk is stored in a single file or split into 2GB files. For example, you may have allocated all the disk space for a virtual disk, then find that you need to reclaim some hard disk space on the host. You can convert the preallocated virtual disk into a growable disk, then remove the original virtual disk file. The new virtual disk is large enough to contain all the data in the original virtual disk. The virtual disk grows in size as you add data to it.
These features and the ability to use scripting to automate management of virtual disks were added to VMware Workstation in version 4.5.2.
You can use the virtual disk manager for the following tasks:
- Automate the management of virtual disks with scripts.
- Create virtual disks that are not associated with a particular virtual machine, to be used as templates, for example.
- Switch the virtual disk type from preallocated to growable, or vice versa. When you change the disk type to growable, you reclaim some space on the virtual disk. You can shrink the virtual disk to reclaim even more disk space.
- Expand the size of a virtual disk so it is larger than the size specified when you created it.
- Defragment virtual disks.
- Prepare and shrink virtual disks without powering on the virtual machine. (Windows hosts only.)
You can use the virtual disk manager with virtual disks created under VMware GSX Server, VMware Workstation and VMware VirtualCenter (provided the virtual disk was created on a GSX Server host managed by VirtualCenter).
You cannot use the virtual disk manager to create physical (raw) disks. Physical disks cannot be shrunk by the virtual disk manager or by Workstation.
For more information about using the virtual disk manager, read the following sections:
Running the VMware Virtual Disk Manager Utility
To run the VMware Virtual Disk Manager utility, open a command prompt or terminal on the host operating system. On a Windows host, change to the directory where you installed your Workstation software. By default, this directory is C:\Program Files\VMware\VMware Workstation.
The command syntax is:
vmware-vdiskmanager [options]
The options you can or must use includethe following:
Options/Parameters
|
Description
|
<diskname>
|
The name of the virtual disk file. The virtual disk file must have a .vmdk
extension.
You can specify a path to the folder where you want to store the disk files.
If you mapped a network share on your host operating system, you can
create the virtual disk on that share by providing the correct path
information with the disk file name.
|
-c
|
Creates the virtual disk. You must use the -a, -s and -t options, and you
must specify the name of the virtual disk (<diskname>).
|
-r
<sourcediskname>
|
Converts the specified virtual disk, creating a new virtual disk as a result.
You must use the -t option to specify the disk type to which the virtual
disk is converted and you must specify the name of the target virtual disk
(<targetdiskname>).
Once the conversion is completed and you have tested the converted
virtual disk to make sure it works as expected, you can delete the original
virtual disk file.
In order for the virtual machine to recognize the converted virtual disk,
you should use the virtual machine settings editor to remove the existing
virtual disk from the virtual machine, then add the converted disk to the
virtual machine. For information on adding virtual disks to a virtual
machine, see Adding Drives to a Virtual Machine.
|
-x <n>[GB|MB]
<diskname>
|
Expands the virtual disk to the specified capacity. You must specify the
new, larger size of the virtual disk in gigabytes or megabytes. You cannot
change the size of a physical (raw) disk.
Caution: Before running the virtual disk manager utility, you should back
up your virtual disk files.
|
-d <diskname>
|
Defragments the specified virtual disk. You can defragment only growable
virtual disks. You cannot defragment preallocated virtual disks.
|
-p <mountpoint>
|
Prepares a virtual disk for shrinking. If the virtual disk is partitioned into
volumes, each volume must be prepared separately. The volume (C: or D:,
for example) must be mounted by VMware DiskMount at
<mountpoint>. After you prepare the volume, unmount it with
VMware DiskMount. Continue mounting each volume of the virtual disk
and preparing it for shrinking until you complete this process for all the
volumes of the virtual disk.
You can mount only one volume of a virtual disk at a time with VMware
DiskMount. You can prepare volumes of virtual disks for shrinking on
Windows hosts only.
|
-k <diskname>
|
Shrinks the specified virtual disk. You can shrink only growable virtual
disks. You can shrink virtual disks on Windows hosts only.
You cannot shrink a virtual disk if the virtual machine has a snapshot. To
keep the virtual disk in its current state, simply remove the snapshot. To
discard changes made since you took the snapshot, revert to the
snapshot.
|
-a
[ide|buslogic|
lsilogic]
|
Specifies the disk adapter type. You must specify an adapter type when
creating a new virtual disk. Choose one of the following types:
· ide - for an IDE adapter.
· buslogic - for a BusLogic SCSI adapter.
· lsilogic - for an LSI Logic SCSI adapter.
|
-s <n>[GB|MB]
|
Specifies the size of the virtual disk. Specify whether the size <n> is in GB
(gigabytes) or MB (megabytes). You must specify the size of a virtual disk
when you create it.
Even though you must specify the size of a virtual disk when you expand
it, you do not use the -s option.
|
-t [0|1|2|3]
|
You must specify the type of virtual disk when you create a new one or
reconfigure an existing one. Specify one of the following disk types:
0 - to create a growable virtual disk contained in a single virtual disk file
1 - to create a growable virtual disk split into 2GB files
2 - to create a preallocated virtual disk contained in a single virtual disk
file
3 - to create a preallocated virtual disk split into 2GB files
|
-q
|
Disables virtual disk manager logging.
If you keep logging enabled, messages generated by the virtual disk
manager are stored in a log file. The name and location of the log file
appear in the command prompt or terminal window after the virtual disk
manager command is run.
|
Shrinking Virtual Disks with VMware Virtual Disk Manager
If the virtual disk is located on a Windows host, you can use the virtual disk manager to prepare and shrink virtual disks. You cannot use the virtual disk manager to prepare or shrink virtual disks located on a Linux host. You cannot use the virtual disk manager to shrink physical disks. Shrinking a virtual disk does not reduce the maximum capacity of the virtual disk itself. For more information about shrinking, see Defragmenting and Shrinking Virtual Disks.
Caution: You cannot shrink a virtual disk if the virtual machine has a snapshot. To
keep the virtual disk in its current state, simply remove the snapshot. To discard
changes made since you took the snapshot, revert to the snapshot.
You must prepare each volume of the virtual disk (drive C: or D:, for example) for shrinking before you can shrink the disk. To prepare a volume for shrinking, you must first mount it. To mount the volume, use the VMware DiskMount Utility, available as a free download from the VMware Web site. Go to www.vmware.com/download/diskmount.html.
The VMware DiskMount user's manual is available from the VMware Web site at www.vmware.com/pdf/VMwareDiskMount.pdf. It contains instructions on mounting and unmounting virtual disk volumes with DiskMount.
VMware DiskMount mounts individual volumes of a virtual disk. For the best results when you shrink of a virtual disk, you should mount all the volumes and prepare them for shrinking.
After you mount a virtual disk volume, use the virtual disk manager to prepare the volume for shrinking. Once you prepare a volume, unmount it, then repeat the process for each volume of the virtual disk. After you prepare all the volumes of the virtual disk, you can shrink the virtual disk. For examples, see Preparing a Virtual Disk for Shrinking and Shrinking a Virtual Disk.
Examples Using the VMware Virtual Disk Manager
The following examples illustrate how to use the virtual disk manager. You run the virtual disk manager from a command prompt.
Creating a Virtual Disk
To create a new virtual disk, use a command like the following:
vmware-vdiskmanager -c -t 0 -s 40GB -a ide myDisk.vmdk
This creates a 40GB IDE virtual disk named myDisk.vmdk. The virtual disk is contained in a single .vmdk file. The disk space is not preallocated.
Converting a Virtual Disk
To convert a virtual disk from preallocated to growable, use a command like the following:
vmware-vdiskmanager -r -t 0 sourceDisk.vmdk targetDisk.vmdk
This converts the disk from its original preallocated type to a growable virtual disk consisting of a single virtual disk file. The virtual disk space is no longer preallocated, and the virtual disk manager reclaims some disk space in the virtual disk so it is only as large as the data contained within it.
Expand the Size of an Existing Virtual Disk
To expand the size of a virtual disk, use a command like the following:
vmware-vdiskmanager -x 40GB myDisk.vmdk
This increases the maximum capacity of the virtual disk to 40GB.
Defragmenting a Virtual Disk
To defragment a virtual disk, use a command like the following:
vmware-vdiskmanager -d myDisk.vmdk
Remember, you cannot defragment a virtual disk if you allocated all the disk space when you created the virtual disk. You cannot defragment a physical disk.
Preparing a Virtual Disk for Shrinking
Before you can shrink a virtual disk, you must prepare each volume on the disk (C: or D:, for example) for shrinking. To prepare a volume, it must be located on a Windows host. First you must mount the volume. To mount the volume, use the VMware DiskMount Utility, available as a free download from the VMware Web site. For information about downloading and using VMware DiskMount, see Shrinking Virtual Disks with VMware Virtual Disk Manager.
VMware DiskMount mounts individual volumes of a virtual disk. For the best results when youl shrink a virtual disk, you should mount all the volumes and shrink them.
After you mount a virtual disk volume, use the virtual disk manager to prepare the disk for shrinking. To prepare the volume mounted as the M: drive for shrinking, use the following command:
vmware-vdiskmanager -p M:
Once the preparations are complete, unmount the volume. Repeat this process for each volume of the virtual disk. After you prepare all the volumes for shrinking, you can shrink the virtual disk.
Shrinking a Virtual Disk
To shrink a virtual disk, it must be located on a Windows host. Before you can shrink the virtual disk, make sure you prepare all the volumes of the virtual disk for shrinking. Then use a command like the following:
vmware-vdiskmanager -k myDisk.vmdk
Remember, you cannot shrink a virtual disk if you allocated all the disk space when you created the virtual disk. You cannot shrink a physical (raw) disk.
If the virtual disk has a snapshot, you cannot shrink the virtual disk. You must remove the snapshot before you shrink the virtual disk.